Internet applications keep crashing

I’m having problems with internet applications at the moment. Is there a virus or other malware going round that could cause this? Any known fixes?

I’m running Windows XP

Syptoms as follows :

IE6 and Firefox crash as soon as I try to load any page. Literally, within one second of the page starting to load. That is, the program acts as if I’d clicked on the close button.

If I turn off the modem, I can run the browser, and work offline. Only when I connect to the internet, and try to access any page, they crash instantly.

Other internet applications, eg email and downloaders run for a while, but they crash after a number of minutes.

I’ve run anti-virus software, it did remove some malware, but this has not solved the problem.

I’ve tried reinstalling Windows. This hasn’t solved the problem. This has reverted my computer to XP SP1 with all recent updates removed.

It’s not a firewall problem, I was using the SP2 firewall, but that’s been removed.

I have a multiboot PC, this has only affected one installation of Windows. I can run windows on a different partition, without the problem. NB: it has affected the partition I use most often. The other has various basckground processes that I use occasionally, but which slow the computer down to a snails pace. I don’t like using this partition unless I have to.

Any ideas?

I’m assuming here when you reinstalled Windows you didn’t nuke what was there, just basically copied over it: I suggest you run scans with at least 3 different AV apps and 3 different spyware apps.

BTW did this just suddenly happen to both browsers at once, out of the blue? Any history to do with the problem’s onset would be useful.